Not for them. I want to improve the world by facilitating various things. For example, I want people to write more and better IMAP clients and use webmail less, so I answer IMAP questions. As it happens I know a lot about IMAP, and put that knowledge to use in a small way.

SO's business model is to make a profit by helping me do such things, and helping others do similarish things. That's a good way to earn a living.